Introduction

Note: This document presents full details of the application profile. For a summary view, see the Dublin Core Collection Description Application Profile Summary [APS].

Collections and collection-level description

The term "collection" can be applied to any aggregation of physical or digital items. Those items may be of any type, so examples might include aggregations of natural objects, created objects, "born-digital" items, digital surrogates of physical items, and the catalogues of such collections (as aggregations of metadata records). The criteria for aggregation may vary: e.g. by location, by type or form of the items, by provenance of the items, by source or ownership, and so on. Collections may contain any number of items and may have varying levels of permanence.

A "collection-level description" provides a description of the collection as a unit: the resource described by a collection-level description is the collection, rather than the individual items within that collection. Collection-level descriptions are referred to in Michael Heaney's An Analytical Model of Collections and their Catalogues as "unitary finding-aids" [AMCC].

Collection-level description enables a collection provider to

disclose information about the content and availability of collections to users where item-level metadata does not exist or is not available, or where the provision of item-level detail is not required or appropriate

It enables a user to

discover and locate collections of interest

select collections to explore on the basis of a summary description

compare collections as broadly similar objects, even where items (and/or item-level metadata) are heterogeneous

understand conditions of access and use

interpret collections (and items within collections)

Increasingly, many of these functions - notably the discovery, location, selection and comparison of collections - are being carried out by software acting on behalf of a human user, perhaps in accordance with user preferences or with parameters describing the scope of a particular service.

A Note on Dublin Core Application Profiles

A Dublin Core Application Profile (DCAP) specifies how some class of DC metadata description sets is constructed, typically the class of description sets which are deployed within a metadata application or within a set of applications and services operating within some domain or community. A DCAP describes:

The set of terms used in a class of DC metadata description sets.

How the terms in this set are deployed in this class of DC metadata description sets. This includes

the types of resources described by descriptions within these description sets,

the properties referenced in statements in those descriptions, and how those properties are used to describe resources of the specfied type.

requirements for the the occurrence of statements using a specified property,

constraints on the sets of values which are referenced in a statement using a specified property (vocabulary encoding schemes), and

constraints on the datatypes of the value strings occurring in a statement using a specified property (syntax encoding schemes).

The terms description set, description, property, value, vocabulary encoding scheme, value representation, rich representation, value string, syntax encoding scheme, and related description are used in the sense they are used in the DCMI Abstract Model [DCAM].

This document is not a description of an XML format. There may be multiple bindings of this DCAP, to XML and to other syntaxes.

Functional Requirements of the DC CD AP

The DC CD AP is intended to provide a means of creating simple descriptions of collections and collection-descriptions suitable for a broad range of collections. It is designed primarily to support the discovery and selection of collections, though it may be used to support other functions such as collection management too. It is not intended to describe every possible characteristic of every type of collection.

The aim is that the DC CD AP should support:

the discovery of collections and collection-descriptions of potential interest, by enabling searching on various attributes of the collection including:

the name or title of the collection or collection-description

the subject and coverage of the collection

the nature or genre of the items within the collection or collection-description

the media type or format of the items within the collection or collection-description

the entity that created the collection or collection-description

the entity that owns the collection or collection-description

relationships between collections, between collection-descriptions and between collections and collection-descriptions

the identification of a known collection or collection-description, by enabling the capture and disclosure of identifying attributes such as

the formal identifier(s) the collection or collection-description

the name or title of the collection or collection-description

a textual description of the collection or collection-description

the selection of one or more collections or collection-descriptions from amongst a number of discovered collections or collection-descriptions, by enabling the capture and disclosure of attributes such as

a textual description of the collection or collection-description

a description of rights held in/over the collection or collection-description and conditions of access and use

a description of the custodial history of the collection or collection-description

a description of the way in which items are added to the collection or collection-description

the identification of the location of the collection or collection-description

the identification of the services that provide access to the collection or collection-description

Data Model

The DC CD AP is based on a data model which is derived from that described in Michael Heaney's An Analytical Model of Collections and their Catalogues [AMCC] and Users and Information Resources: An Extension of the Analytical Model of Collections and their Catalogues into Usage and Transactions [EAMCC]. The model used here is both a subset and a simplification of that model. The entity type which in that model is referred to as "Resource Mediator" is referred to here as "Service".

Figure 1 illustrates the primary entity types and their relationships:

Fig 1: The DC CD AP Data Model

The following definitions are used (adapted from the Analytic Model):

Collection An aggregation of Items.

Item The concrete realisation of Content.

Location A place where a Collection is held.

Service A system that provides access to the Items within the Collection

Collection-Description A resource which describes a Collection.

In the Analytic Model relationships may carry attributes; in the DC CD AP, relationships are represented as simple properties and do not themselves carry attributes, so some of the expressivity of the model is lost in the metadata schema.

The DC CD AP describes the use of properties to represent attributes of the collection and of the collection-description, and relationships between collections, between collections and collection-descriptions, and between collections, collection-descriptions and other entities. It does not describe how to represent attributes of other entities in the model.

More specifically, the DC CD AP supports the description of those types of collection-description which are themselves collections, i.e. they are aggregations of items which are descriptions of other resources i.e. they are items of metadata.

Figure 2 summarises the relationship between a collection and collection-description and their constituent items. The relationship between an item in the collection-description and an item in the (described) collection varies depending on the nature of the collection-description. In some cases, there may be fairly simple correspondences between items in the collection-description and items in the described collection; in other cases the metadata items in the collection-description may describe groupings of items within the described collection as well as individual items, or indeed the individual items may not be described at all. Further, a collection-description which is itself a collection may be described by a second collection-description. For a more detailed discussion of the nature of collection-descriptions, see the Analytical Model [AMCC]

Fig 2: Collections and Collection-Descriptions

The Dublin Core Collection Description Application Profile (DC CD AP)

The DC CD AP specifies how to construct a DC metadata description set that includes:

a description of one or more collections (aggregations of items)

a description of zero or more collection-descriptions (resources which describe collections) (N.B. a collection-description is not necessarily a DC metadata description)

A description set conforming to this DCAP must contain at least one description of a collection. It may contain descriptions only of collections and collection-descriptions, or it may also include descriptions of resources of other types, related to those collections or collection-descriptions, which are referred to as values in statements about the collections or collection-descriptions. Such other resources might include the location of a collection, the services that provide access to a collection, concepts that are the subject of a collection, and agents related to the collection or collection-description. While this DCAP permits the inclusion of descriptions of those related resources in a description set, it does not specify the terms to be referenced in descriptions of resources other than collections and collection-descriptions.

The metadata terms referenced in the DC CD AP are drawn from the DCMI metadata vocabularies and also from other metadata vocabularies owned by other agencies.

The DC CD AP is independent of any particular syntax for representing description sets. Description sets conforming to the DC CD AP may be represented using any of the conventions recommended by DCMI for expressing DC metadata based on the DCMI Abstract Model.

Vocabularies/Namespaces used in this DCAP

All references to properties and classes in DC metadata descriptions are made using URIs, In this document, Qualified Names of the form prefix ":" local-part are sometimes used as abbreviations for URIs which identify metadata terms. Prefixes are assumed to be associated with Namespace Names (URIs) as follows, and the corresponding URI for the term is constructed by concatenating the Namespace Name and the local-part:

Vocabulary Title

Namespace Name

Prefix

The Dublin Core Metadata Element Set, v1.1

http://purl.org/dc/elements/1.1/

dc

Dublin Core Terms

http://purl.org/dc/terms/

dcterms

Dublin Core Type Vocabulary

http://purl.org/dc/dcmitype/

dcmitype

MARC Relator Code Properties

http://www.loc.gov/loc.terms/relators/

marcrel

Collection Description Terms

http://purl.org/cld/terms/

cld

Collection Description Type Vocabulary Terms

http://purl.org/cld/cdtype/

cdtype

How to Read the Tables in this Document

The two sections "Describing a Collection" and "Describing a Collection-Description" each describe how a set of terms (properties, classes, vocabulary encoding schemes, syntax encoding schemes) is used to construct a DC metadata description of a resource of the specified type.

The first table in each of these sections describes the class, the type of resource, to which the metadata description applies.

Class URI: The URI by which the class is referenced in a DC metadata description.

Qualified Name for Class: The Qualified Name which is typically used as an abbreviation for the class URI.

Defined By: The name and identifier of the metadata vocabulary from which the class is drawn.

Type of Term: An indication of the type of the term, according to the typology of the DCMI Abstract Model

Subclass Of: Class of which the current class is a subclass.

Label: The short label provided for the class by its owner/maintenance agency.

Definition: The definition provided for the class by its owner/maintenance agency.

Comments: Additional information about the class provided by its owner/maintenance agency.

See Also: A resource which provides further information about the class.

Each subsequent table in the section describes how a specified property is used in a statement within a DC metadata description. The use of the property is described using the following attributes:

Property URI: The URI by which the property is referenced in a DC metadata description.

Qualified Name for Property: A unique name/identifier for the property. It is presented as a Qualified Name, but is an abbreviation for the property URI.

Defined By: The name and identifier of the metadata vocabulary from which the property is drawn.

Type of Term: An indication of the type of the term, according to the typology of the DCMI Abstract Model

Subproperty Of: A property of which the current property is a subproperty.

Source Label: The short label provided for the property by its owner/maintenance agency.

Label in this DCAP: A short human-readable label that provides an indication of how the property is to be used in a DC metadata description of a resource of the specified type. The label does not appear in the description. It may be used to provide a descriptor for fields in displays of descriptions to human readers, but there is no requirement for display applications to use this label.

Source Definition: The definition provided for the property by its owner/maintenance agency.

Usage in this DCAP: A description of how the property is to be applied in a description of a resource of the specified type. This information supplements the definition of the property provided by its owner/maintenance agency.

Comments for this DCAP: Additional information about the use of the property in a description of a resource of the specified type, typically on the values and their representation.

Uses Vocabulary Encoding Scheme: The unique names/identifiers of vocabulary encoding schemes from which values for the property should be drawn. Names are presented as Qualified Names, but are abbreviations for URIs. The URI is used to refer to the vocabulary encoding scheme in DC metadata descriptions. If no vocabulary encoding scheme is listed, then the DCAP does not specify a vocabulary encoding scheme from which values should be drawn. However the definition and usage of the property may determine that values of only certain types are appropriate. For example, the value of the dc:creator property must be an entity capable of action.

Value URI: An indication of whether, if a statement using the property (and vocabulary encoding scheme, where specified) is present, a value URI is to be used. Mandatory - a value URI is required; Mandatory, Fixed - a specified value URI is required; Optional = a value URI is optional (see note); Not permitted = a value URI is not permitted

Value String: An indication of whether, if a statement using the property (and vocabulary encoding scheme, where specified) is present, a value string is to be used. Mandatory - a value string is required; Mandatory, Fixed - a specified value string is required; Optional = a value string is optional (see note); Not permitted = a value string is not permitted

Syntax Encoding Scheme(s): The unique names/identifiers of datatypes from which value strings for the property should be drawn. Names are presented as Qualified Names, but are abbreviations for URIs. The URI is used to refer to the datatype in DC metadata descriptions. If no datatype is listed, then the DCAP does not specify a datatype from which value strings should be drawn.

Rich Representation: An indication of whether, if a statement using the property (and vocabulary encoding scheme, where specified) is present, a rich representation is to be used. Mandatory - a rich representation is required; Optional = a rich representation is optional (see note); Not permitted = a rich representation is not permitted

Obligation: An indication of whether a statement using this property is required in a DC metadata description. Mandatory = a statement using this property is required, Optional/Recommended = a statement using this property is optional but recommended, Optional = a statement using this property is optional

Condition: Information on any additional conditions on the obligation to include a statement referencing the property in a description of a resource of the specified type

Minimum Occurrences: The minimum number of statements referencing this property that can occur in a description of a resource of the specified type

Maximum Occurrences: The maximum number of statements referencing this property that can occur in a description of a resource of the specified type

Note: For each value, at least one of the following components must be present: a value URI, a rich representation, a value string or a (related) description.

The following two sections describe the vocabulary encoding schemes and syntax encoding schemes referenced in the previous two sections.

Vocabulary Encoding Scheme URI: The URI by which the vocabulary encoding scheme is referenced in a DC metadata description.

Qualified Name for Vocabulary Encoding Scheme: The Qualified Name which is typically used as an abbreviation for the class URI.

Defined By: The name and identifier of the metadata vocabulary from which the vocabulary encoding scheme is drawn.

Type of Term: An indication of the type of the term, according to the typology of the DCMI Abstract Model

Label: The short label provided for the vocabulary encoding scheme by its owner/maintenance agency.

Definition: The definition provided for the vocabulary encoding scheme by its owner/maintenance agency.

Comments for this DCAP: Additional information about the use of the vocabulary encoding scheme in this DCAP.

See Also: A resource which provides further information about the vocabulary encoding scheme.

Used as Vocabulary Encoding Scheme For: The type of resource and the property for which the vocabulary encoding scheme provides values.

Syntax Encoding Scheme URI: The URI by which the syntax encoding scheme is referenced in a DC metadata description.

Qualified Name for Syntax Encoding Scheme: The Qualified Name which is typically used as an abbreviation for the class URI.

Defined By: The name and identifier of the metadata vocabulary from which the syntax encoding scheme is drawn.

Type of Term: An indication of the type of the term, according to the typology of the DCMI Abstract Model

Label: The short label provided for the syntax encoding scheme by its owner/maintenance agency.

Definition: The definition provided for the syntax encoding scheme by its owner/maintenance agency.

Comments for this DCAP: Additional information about the use of the syntax encoding scheme in this DCAP.

See Also: A resource which provides further information about the syntax encoding scheme.

Used as Syntax Encoding Scheme For: The type of resource and the property for which the syntax encoding scheme provides value strings.

Describing a Collection

Collection [dcmitype:Collection]

Class URI

http://purl.org/dc/dcmitype/Collection

Qualified Name for Class

dcmitype:Collection

Defined By

DCMI Type Vocabulary
http://purl.org/dc/dcmitype/

Type of Term

Class

SubClass Of

[n/a]

Label

Collection

Definition

A collection is an aggregation of items. The term collection means that the resource is described as a group; its parts may be separately described and navigated.

A collection identifier must be a URI, using a URI scheme that has been registered with IANA.

The URI of the collection should be used as the resource URI of the description and also as the value string in a statement using the dc:identifier property.

If multiple URIs are assigned to a collection, one of the URIs should be used as the resource URI, and each URI, including the resource URI, should be used as the value string in a separate statement using the dc:identifier property.

To record titles in multiple languages, use multiple statements and in each statement associate the value string with the appropriate language tag.

Where an existing name is used, the value string should preserve the original wording, order and spelling of an existing name. Punctuation need not reflect the usage of the original. Subtitles should be separated from the title by a sequence of space-colon-space, for example:

Voices from the Dust Bowl: The Charles L. Todd and Robert Sonkin Migrant Worker Collection

A date range should be supplied in the form described by RKMS-ISO8601. Start dates and end dates should be in the form of a date or date-time combination as specified by W3CDTF. Start dates and end dates should be separated by a solidus (forward slash) (/). Either the start date or the end date may be omitted to indicate an open-ended date range.

A range of dates over which the individual items within the collection were created.

Usage in this DCAP

[n/a]

Comments for this DCAP

A value string must be provided.

A date range should be supplied in the form described by RKMS-ISO8601. Start dates and end dates should be in the form of a date or date-time combination as specified by W3CDTF. Start dates and end dates should be separated by a solidus (forward slash) (/). Either the start date or the end date may be omitted to indicate an open-ended date range.

A collection-description identifier must be a URI, using a URI scheme that has been registered with IANA.

The URI of the collection-description should be used as the resource URI of the description and also as the value string in a statement using the dc:identifier property.

If multiple URIs are assigned to a collection-description, one of the URIs should be used as the resource URI, and each URI, including the resource URI, should be used as the value string in a separate statement using the dc:identifier property.

The nature or genre of the content of one or more items within the collection.

Usage in this DCAP

The nature or genre of the content of one or more items within the collection-description.

Comments for this DCAP

A value string must be provided; a value URI may also be provided.

Where the collection-description includes items of multiple types, a separate statement should be used for each type which is regarded as significant for a user of the collection-description description.

The media type, physical or digital, of one or more items within the collection-description.

Usage in this DCAP

[n/a]

Comments for this DCAP

A value string must be provided; a value URI may also be provided.

Where the collection-description includes items of multiple media types, a separate statement should be used for each media type which is regarded as significant for a user of the collection-description description.

A range of dates over which the collection-description was accumulated.

Comments for this DCAP

A value string must be provided.

A date range should be supplied in the form described by RKMS-ISO8601. Start dates and end dates should be in the form of a date or date-time combination as specified by W3CDTF. Start dates and end dates should be separated by a solidus (forward slash) (/). Either the start date or the end date may be omitted to indicate an open-ended date range.

A range of dates over which the individual items within the collection were created.

Usage in this DCAP

A range of dates over which the individual items within the collection-description were created.

Comments for this DCAP

A value string must be provided.

A date range should be supplied in the form described by RKMS-ISO8601. Start dates and end dates should be in the form of a date or date-time combination as specified by W3CDTF. Start dates and end dates should be separated by a solidus (forward slash) (/). Either the start date or the end date may be omitted to indicate an open-ended date range.

Administrative Metadata

A description set conforming to this profile should itself be described by an appropriate administrative metadata description. This document does not specify the properties to be used in that administrative metadata description.